1. Field of the Invention
The present invention relates to integrated circuit technology. More particularly, the present invention relates to on-chip circuitry for sensing an analog signal during powerup of an integrated circuit.
2. The Prior Art
There sometimes exists a need for sensing an analog signal present in an integrated circuit during powerup of the integrated circuit prior to a time at which the entire circuit is functioning. In some cases, an additional I/O pad may be provided to provide power for performing this function. However, as the complexity of the functions of the integrated circuit increases, integrated circuit I/O availability becomes more constrained and additional I/O to provide functionality such as application of external power supply potential may not be available.